Which carbohydrate forms the cell walls of plants?

Which carbohydrate forms the cell walls of plants?

• A. Lignin
• B. Chitin
• C. Cellulose
• D. Peptidoglycan

Answer: (C)

Plants build their cell walls mainly from cellulose, a long polymer of glucose units linked by beta-1,4-glycosidic bonds. These straight chains aggregate into microfibrils that form a strong, fibrous network, providing shape and mechanical strength to plant cells. Lignin strengthens and waterproofs the wall but is not a carbohydrate. Chitin is a nitrogen-containing polysaccharide found in fungal cell walls and in arthropod exoskeletons, not plant walls. Peptidoglycan forms the bacterial cell wall, a mesh of sugars and peptides. So the carbohydrate that forms the structural framework of plant cell walls is cellulose.

Plants build their cell walls mainly from cellulose, a long polymer of glucose units linked by beta-1,4-glycosidic bonds. These straight chains aggregate into microfibrils that form a strong, fibrous network, providing shape and mechanical strength to plant cells. Lignin strengthens and waterproofs the wall but is not a carbohydrate. Chitin is a nitrogen-containing polysaccharide found in fungal cell walls and in arthropod exoskeletons, not plant walls. Peptidoglycan forms the bacterial cell wall, a mesh of sugars and peptides. So the carbohydrate that forms the structural framework of plant cell walls is cellulose.